Hunting around for information on scientology / autism I cam across this guy’s posts that have a bit of research. He suggests that DAN (Defeat Autism Now) & the anti-mercury crowd have been heavily infiltrated with scientologists.
ETA: He’s a blogger on the topic of autism
Take it for what you will, but he does have some interesting cited research in there. See the weblink to see the actual weblinks to some of his sources.